There exist many situations where emergency respirator apparatus are desired, if not necessary. For instance, miners or firemen are constantly exposing themselves to circumstances where the risk of a toxic atmosphere exists. With only a moment's notice, it may be necessary for miners or firemen to extricate themselves from a position where deadly gases and visually irritating or damaging fumes are present.
Many emergency respirators or masks, currently on the market, fail to provide adequate protection from deadly gases and visually damaging fumes present in the atmosphere. In addition, many of these emergency respirators are complex to manufacture and complex in design.
In U.S. Pat. No. 2,852,023 to Hamilton, et al., there is shown a pendulum breathing-type escape apparatus having a mouthpiece supporting a KO.sub.2 type canister and a breathing bag. The canister is not contained inside the breathing bag, but in series with the mouthpiece and the breathing bag. An oxygen charge supplements the oxygen produced by the chemical processing of the exhalation breath through the canister. There is no hood disclosed to protect the vision of a wearer if the circumstances require it.
U.S. Pat. No. 3,893,459 to Mausteller, et al. discloses an emergency breathing apparatus that uses circuitous breathing. A breathing bag is attached to one end of a chemical cartridge to receive processed exhalation. A mask with a breathing opening fits over the nose and mouth and possibly over the face of a wearer. The breathing opening communicates with a check valve surrounded by a perforated wall. Exhalation passes through the breathing opening and through the perforated wall into the chemical to be processed. After processing it collects in the breathing bag. The oxygen is then inhaled from the bag through the check-valve, which opens for inhalation, and through the breathing tube into the mouth or nose of a user.
U.S. Pat. No. 4,411,023 to Dinson discloses a smoke protective hood for protecting a wearer from poisonous fumes. The hood is not self-contained and no breathing bag is utilized. The protection offered by the mask is limited to toxic gases that are absorbed by materials such as coconut charcoal, silica and almondine. These materials fit into the mask itself at a location before the mouth of the user.